Recently, DVB-C2 (next generation digital cable transmission system being developed by the DVB Project) Standard is under progress. An agreement is made that DVB-C2 shall reuse the content of DVB-T2 Standard as much as possible. As a result, OFDM technique will be adopted as well as the coding technique (BCH+LDPC) specified in DVB-T2 Standard. However, it must be noted that DVB-T2 Standard is designed for using in the terrestrial wireless channel while the DVB-C2 Standard is designed for using in the cable channel. Cable channels differ from wireless channels in two aspects. First, cable channel is a high quality (high SNR) channel with only a few weak echoes. Second, the wireless spectrum assigned for TV broadcasting is confined by FCC while we can use the spectrum with high freedom in the cable networks. Consequently, the signal frame structure and preambles used in DVB-T2 may not be suitable to be reused in DVB-C2 Standard.